U.S. patent application number 13/054981 was filed with the patent office on 2011-05-26 for compressor.
Invention is credited to Yongchol Kwon, Geun-Hyoung Lee, Kangwook Lee, Jin-Ung Shin.
Application Number | 20110123366 13/054981 |
Document ID | / |
Family ID | 42085119 |
Filed Date | 2011-05-26 |
United States Patent
Application |
20110123366 |
Kind Code |
A1 |
Lee; Kangwook ; et
al. |
May 26, 2011 |
COMPRESSOR
Abstract
A compressor eliminates sliding contacts between a cylinder
(132) and a roller (142) to minimize the mixing of lubricating oil
into refrigerant, and is structured to evenly distributing
lubricating oil over sliding contact portions of a compressor
actuator by pumping the oil from the inside on an axis of rotation
(141), the compressor comprising: a hermetic container (110)
storing oil at a lower portion; a stator (120) mounted within the
hermetic container (110); a cylinder type rotor (130) rotating
within the stator (120) by a rotating electromagnetic field from
the stator (120), with the rotor (130) defining a compression
chamber inside; a roller (142) rotating within the compression
chamber of the cylinder type rotor (130) by a rotational force
transferred from the rotor (130), with the roller (142) compressing
refrigerant during rotation; an axis of rotation (141) integrally
formed with the roller (142) and extending in an axial direction; a
vane (143) dividing the compression chamber into a suction region
where refrigerant is sucked in and a compression region where the
refrigerant is compressed/discharged from, with the vane (143)
transferring the rotational force from the cylinder type rotor to
the roller (142); and oil feed passages provided to the axis of
rotation (141) and the roller (142), with the oil feed passage
feeding oil that is pumped along the motion of the axis of rotation
(141) to an area where two or more members are slid onto within the
compression chamber.
Inventors: |
Lee; Kangwook; (Changwon-si,
KR) ; Shin; Jin-Ung; (Changwon-si, KR) ; Kwon;
Yongchol; (Changwon-si, KR) ; Lee; Geun-Hyoung;
(Busan, KR) |
Family ID: |
42085119 |
Appl. No.: |
13/054981 |
Filed: |
November 28, 2008 |
PCT Filed: |
November 28, 2008 |
PCT NO: |
PCT/KR08/07015 |
371 Date: |
January 20, 2011 |
Current U.S.
Class: |
417/356 |
Current CPC
Class: |
F04C 15/0007 20130101;
F04C 18/322 20130101; F04C 27/008 20130101; F04C 29/0085 20130101;
F01C 21/0809 20130101; F04C 2240/603 20130101; F04C 18/32 20130101;
F04C 29/023 20130101; F04C 18/3564 20130101; F04C 18/348 20130101;
F04C 23/008 20130101; F04C 29/0057 20130101; F04C 18/3443
20130101 |
Class at
Publication: |
417/356 |
International
Class: |
F04C 18/356 20060101
F04C018/356 |
Claims
1. A compressor, comprising: a hermetic container storing oil at a
lower portion; a stator mounted within the hermetic container; a
cylinder type rotor rotating within the stator by a rotating
electromagnetic field from the stator, with the rotor defining a
compression chamber inside; a roller rotating within the
compression chamber of the cylinder type rotor by a rotational
force transferred from the rotor, with the roller compressing
refrigerant during rotation; an axis of rotation integrally formed
with the roller and extending in an axial direction; a vane
dividing the compression chamber into a suction region where
refrigerant is sucked in and a compression region where the
refrigerant is compressed/discharged from, with the vane
transferring the rotational force from the cylinder type rotor to
the roller; and oil feed passages provided to the axis of rotation
and the roller, with the oil feed passage feeding oil that is
pumped along the motion of the axis of rotation to an area where
two or more members are slid onto within the compression
chamber.
2. The compressor according to claim 1, wherein the axis of
rotation is extended from both axial sides of the roller, with the
compressor further comprising: first and second covers joined to
the cylinder type rotor in the axial direction, with the covers
defining the compression chamber therebetween and receiving the
axis of rotation therethrough; and first and second bearings joined
to the first and second covers for rotatably supporting the axis of
rotation, the roller, and the first and second covers onto the
hermetic container.
3. The compressor according to claim 2, wherein the oil feed
passage comprises an oil feeder formed within the axis of rotation
that is protruded from one side of the roller in the axis
direction, and a first oil feed hole radially passing through one
portion of the axis of rotation that is contiguous with the roller
to be in communication with the oil feeder.
4. The compressor according to claim 3, wherein the oil feed
passage further comprises first oil storage cavities formed in the
axis of rotation having the first oil feed hole and in one axial
side of the roller, with the roller being connected to the axis of
rotation, so as to temporarily collect oil supplied through the
first oil feed hole.
5. The compressor according to claim 4, wherein the oil feed
passage further comprises a second oil feed hole axially passing
through the second rotating member to be in communication with the
first oil storage cavities, and second oil storage cavities formed
in the other axial side of the second rotating member having the
second oil feed hole and in the axis of rotation connected thereto
so as to temporarily collect oil supplied through the second feed
hole.
6. The compressor according to claim 5, wherein the second oil
storage cavities are formed to lubricate a bearing in contact with
the axis of rotation and the other axial side of the roller.
7. The compressor according to claim 1, wherein the axis of
rotation is extended from one axial side of the roller, the
compressor further comprising: a shaft cover and a main cover
joined to the cylinder type roller and the roller in the axial
direction for defining a compression chamber therebetween, with the
shaft cover covering the axis of rotation, with the main cover
receiving the axis of rotation; a mechanical seal axially joined to
the shaft cover and rotatably supporting the shaft cover onto the
hermetic container; and a bearing axially joined to the main cover
and rotatably supporting the main cover, the axis of rotation and
the roller onto the hermetic container.
8. The compressor according to claim 7, wherein the oil feed
passage comprises an oil feeder formed within the axis of rotation
in the axis direction, and a first oil feed hole radially passing
through one portion of the axis of rotation that is contiguous with
the roller to be in communication with the oil feeder.
9. The compressor according to claim 8, wherein the oil feed
passage further comprises first oil storage cavities formed in the
axis of rotation having the first oil feed hole and in one axial
side of the roller, with the roller being connected to the axis of
rotation, so as to temporarily collect oil supplied through the
first oil feed hole.
10. The compressor according to claim 4, wherein the first oil
storage cavities are formed to lubricate a bearing in contact with
an outer circumferential surface of the axis of rotation and with
one axial side of the second rotating member.
11. The compressor according to claim 10, wherein the oil feed
passage further comprises a second oil feed hole axially passing
through the second rotating member to be in communication with the
first oil storage cavities, and second oil storage cavities formed
in the other axial side of the roller having the second oil feed
hole so as to temporarily collect oil supplied through the second
feed hole.
12. The compressor according to claim 11, wherein the second oil
storage cavities are formed to lubricate a bearing in contact with
the axis of rotation and with the other axial side of the
roller.
13. The compressor according to claim 12, wherein the shaft cover
has cavities for storing oil which are formed on an opposite side
of the second oil storage cavities.
14. The compressor according to claim 11, wherein the oil feed
passage further comprises oil feed cavities provided to the roller
and the vane so as to communicate with at least one of the first
and second oil storage cavities.
15. The compressor according to claim 3, wherein the oil feed
passage is mounted with an oil feed member for pumping oil up to an
oil feeder, with the oil feed member being twisted in a spiral
shape.
16. The compressor according to claim 3, wherein the oil feeder
feeds oil through the oil feed passage by a capillary
phenomenon.
17. The compressor according to claim 16, wherein the oil feeder
has a groove in an inner circumferential thereof, and an oil feed
member is press fitted therein except for the groove.
18. The compressor according to claim 16, wherein the oil feed
member having a groove in an outer circumferential surface is press
fitted into the oil feeder.
19. The compressor according to claim 1, further comprising: a
refrigerant suction passage for sucking refrigerant into the
compression chamber through the axis of rotation and the roller,
with the refrigerant suction passage formed separately from an oil
feed passage.
20. A compressor, comprising: a hermetic container storing oil at a
lower portion; a stator secured within the hermetic container; a
first rotating member rotating, by a rotating electromagnetic field
from the stator, about a first axis of rotation which is collinear
with a center of the stator and extended in a longitudinal
direction, with the first rotating member comprising a first cover
and a second cover secured to upper and lower portions for rotating
as one unit; a second rotating member rotating within the first
rotating member by a rotational force transferred from the first
rotating member, with the second rotating member rotating about a
second axis of rotation which is extended through the first and
second covers and compressing refrigerant in a compression chamber
which is defined between the first and second rotating members; a
vane dividing the compression chamber into a suction region where
refrigerant is sucked in and a compression region where the
refrigerant is compressed/discharged from, with the vane
transferring the rotational force from the first rotating member to
the second rotating member; a refrigerant suction passage for
sucking refrigerant into the compression chamber through the second
axis of rotation and the second rotating member; and oil feed
passages provided, in separation from the refrigerant suction
passage, to the second axis of rotation and the second rotating
member, with the oil feed passage feeding oil to an area where two
or more members are slid onto within an oil compression
chamber.
21. A compressor, comprising: a hermetic container storing oil at a
lower portion; a stator secured within the hermetic container; a
first rotating member rotating, by a rotating electromagnetic field
from the stator, about a first axis of rotation which is collinear
with a center of the stator and extended in a longitudinal
direction, with the first rotating member comprising a shaft cover
and a main cover secured in an axial direction; a second rotating
member rotating within the first rotating member by a rotational
force transferred from the first rotating member, with the second
rotating member rotating about a second axis of rotation which is
extended through the cover and compressing refrigerant in a
compression chamber which is defined between the first and second
rotating members; a vane dividing the compression chamber into a
suction region where refrigerant is sucked in and a compression
region where the refrigerant is compressed/discharged from, with
the vane transferring the rotational force from the first rotating
member to the second rotating member; a refrigerant
suction/discharge passage for sucking/discharging refrigerant
into/from the compression chamber through a suction port and a
discharge port formed in the shaft cover; and oil feed passages
provided, in separation from the refrigerant suction/discharge
passages, to the second axis of rotation and the second rotating
member, with the oil feed passage feeding oil to an area where two
or more members are slid onto within an oil compression chamber.
Description
TECHNICAL FIELD
[0001] The present invention relates in general to a compressor,
and more particularly, to a compressor which eliminates sliding
contacts between a cylinder and a roller to minimize the mixing of
lubricating oil into refrigerant, and is structured to be able to
evenly distributing lubricating oil over sliding contact portions
of a compressor actuator by pumping the oil from the inside on an
axis of rotation.
[0002] In addition, the present invention relates to a compressor
having a structure to accommodate a refrigerant passage separately
from an oil feed passage such that the mixing of oil into
refrigerant is minimized and the operational reliability is
enhanced.
BACKGROUND ART
[0003] In general, a compressor is a mechanical apparatus that
receives power from a power generation apparatus such as an
electric motor, a turbine or the like and compresses air,
refrigerant or various operation gases to raise a pressure. The
compressor has been widely used in electric home appliances such as
a refrigerator and an air conditioner, or in the whole
industry.
[0004] The compressors are roughly classified into a reciprocating
compressor wherein a compression chamber to/from which an operation
gas is sucked and discharged is defined between a piston and a
cylinder and refrigerant is compressed as the piston linearly
reciprocates inside the cylinder, a rotary compressor which
compresses an operation gas in a compression chamber defined
between an eccentrically-rotated roller and a cylinder, and a
scroll compressor wherein a compression chamber to/from which an
operation gas is sucked and discharged is defined between an
orbiting scroll and a fixed scroll and refrigerant is compressed as
the orbiting scroll rotates along the fixed scroll.
[0005] Although the reciprocating compressor is excellent in
mechanical efficiency, its reciprocating motion causes serious
vibrations and noise problems. Because of this problem, the rotary
compressor has been developed as it has a compact size and
demonstrates excellent vibration properties.
[0006] The rotary compressor is configured in a manner that a motor
and a compression mechanism part are mounted on a drive shaft in a
hermetic container, a roller fitted around an eccentric portion of
the drive shaft is positioned inside a cylinder that has a cylinder
shape compression chamber therein, and at least one vane is
extended between the roller and the compression chamber to divide
the compression chamber into a suction region and a compression
region, with the roller being eccentrically positioned in the
compression chamber. In general, vanes are supported by springs in
a recess of the cylinder to pressurize surface of the roller, and
the vane(s) as noted above divide(s) the compression chamber into a
suction region and a compression region. In general, vanes are
supported by springs in a recess of the cylinder to pressurize
surface of the roller, and the vane(s), as noted above, divide(s)
the compression chamber into a suction region and a compression
region. The suction region expands gradually with the rotation of
the drive shaft to suck refrigerant or a working fluid into it,
while the compression region shrinks gradually at the same time to
compress refrigerant or a working fluid in it.
[0007] In such a conventional rotary compressor, the eccentric
portion of the drive shaft continuously makes a sliding contact,
during its rotation, with an interior surface of a stationary
cylinder where the roller is secured and with the tip of the vane
where the roller is also secured. A high relative velocity is
created between constituent elements making a sliding contact with
each other, and this generates frictional loss, eventually leading
to degradation of compressor efficiency. Also, there is still a
possibility of a refrigerant leak at the contact surface between
the vane and the roller, thereby causing degradation of mechanical
reliability.
[0008] Unlike the conventional rotary compressors subject to
stationary cylinders, U.S. Pat. No. 7,344,367 discloses a rotary
compressor having a compression chamber positioned between a rotor
and a roller rotatably mounted on a stationary shaft. In this
patent, the stationary shaft extends longitudinally inwardly within
a housing and a motor includes a stator and a rotor, with the rotor
being rotatably mounted on the stationary shaft within the housing
the roller being rotatably mounted on an eccentric portion that is
integrally formed with the stationary shaft. Further, a vane is
interposed between the rotor and the roller to let the roller
rotate along with the rotation of the roller, such that a working
fluid can be compressed within the compression chamber. However,
even in this patent, the stationary shaft still makes a sliding
contact with an interior surface of the roller so a high relative
velocity is created between them and the patent still shares the
problems found in the conventional rotary compressor.
[0009] Meanwhile, WO2008/004983 discloses another type of rotary
compressors, comprising: a cylinder, a rotor mounted in the
cylinder to rotate eccentrically with respect to the cylinder, and
a vane positioned within a slot which is arranged at the rotor, the
vane sliding against the rotor, wherein the vane is connected to
the cylinder to transfer a force to the cylinder rotating along
with the rotation of the rotor, and wherein a working fluid is
compressed within a compression chamber defined between the
cylinder and the rotor. However, these rotary compressors require a
separate electric motor for driving the rotor because the rotor
rotates by a drive force transferred through the drive shaft. That
is, when it comes to the rotary compressor in accordance with the
disclosure, a separate electric motor is stacked up in the height
direction about the compression mechanism part consisting of the
rotor, the cylinder and the vane, so the total height of the
compressor inevitably increases, thereby making difficult to
achieve compact design.
[0010] Moreover, rotary compressors require lubrication to reduce
frictional force and frictional heat between members that make a
sliding contact while rotating. In a conventional compressor, the
roller and the cylinder are typical members making a sliding
contact so an interior of the compression chamber had to be
lubricated, and this made it unavoidable the mixing of refrigerant
and lubricating oil. On account of this, an accumulator had to be
installed additionally to separate the refrigerant from the
lubricating oil, which required extra large compressors and became
the leading cause of manufacturing cost.
[0011] Besides, in case the electromotive mechanism and the
compression mechanism are connected with a drive shaft and
laminated in the height direction, an oil pump and an oil feed
passage had to be provided additionally. Also, with the approach of
pumping up the lubricating oil stored at the bottom of the interior
of the housing and then scattering the oil upward to feed it to the
compression mechanism, the lubricating oil could not be distributed
evenly over the sliding contact portions.
DISCLOSURE OF INVENTION
Technical Problem
[0012] The present invention is conceived to solve the
aforementioned problems in the prior art. An object of the present
invention is to provide a compressor
[0013] which eliminates sliding contacts between a cylinder and a
roller thereby minimizing the mixing of lubricating oil into
refrigerant, and is structured a structure to be able to evenly
distributing lubricating oil over sliding contact portions.
[0014] Another object of the present invention is to provide a
compressor having a structure of high oil recovery and enhanced
operational reliability by minimizing the mixing of oil into
refrigerant.
Technical Solution
[0015] An aspect of the present invention provides a compressor,
comprising: a hermetic container storing oil at a lower portion; a
stator mounted within the hermetic container; a cylinder type rotor
rotating within the stator by a rotating electromagnetic field from
the stator, with the rotor defining a compression chamber inside; a
roller rotating within the compression chamber of the cylinder type
rotor by a rotational force transferred from the rotor, with the
roller compressing refrigerant during rotation; an axis of rotation
integrally formed with the roller and extending in an axial
direction; a vane dividing the compression chamber into a suction
region where refrigerant is sucked in and a compression region
where the refrigerant is compressed/discharged from, with the vane
transferring the rotational force from the cylinder type rotor to
the roller; and oil feed passages provided to the axis of rotation
and the roller, with the oil feed passage feeding oil that is
pumped along the motion of the axis of rotation to an area where
two or more members are slid onto within the compression
chamber.
[0016] The compressor of in accordance with the first embodiment of
the present invention further comprises: first and second covers
joined to the cylinder type rotor in the axial direction, with the
covers defining the compression chamber therebetween and receiving
the axis of rotation therethrough; and first and second bearings
joined to the first and second covers for rotatably supporting the
axis of rotation, the roller, and the first and second covers onto
the hermetic container.
[0017] In the compressor of in accordance with the first embodiment
of the present invention, the oil feed passage comprises an oil
feeder formed within the axis of rotation that is protruded from
one side of the roller in the axis direction, and a first oil feed
hole radially passing through one portion of the axis of rotation
that is contiguous with the roller to be in communication with the
oil feeder.
[0018] In the compressor of in accordance with the first embodiment
of the present invention, the oil feed passage further comprises
first oil storage cavities formed in the axis of rotation having
the first oil feed hole and in one axial side of the roller, with
the roller being connected to the axis of rotation, so as to
temporarily collect oil supplied through the first oil feed
hole.
[0019] In the compressor of in accordance with the first embodiment
of the present invention, the first oil storage cavities are formed
to lubricate a bearing in contact with an outer circumferential
surface of the axis of rotation and with one axial side of the
second rotating member.
[0020] In the compressor of in accordance with the first embodiment
of the present invention, the oil feed passage further comprises a
second oil feed hole axially passing through the second rotating
member to be in communication with the first oil storage cavities,
and second oil storage cavities formed in the other axial side of
the second rotating member having the second oil feed hole and in
the axis of rotation connected thereto so as to temporarily collect
oil supplied through the second feed hole.
[0021] In the compressor of in accordance with the first embodiment
of the present invention, the second oil storage cavities are
formed to lubricate a bearing in contact with the axis of rotation
and the other axial side of the roller.
[0022] In the compressor of in accordance with the first embodiment
of the present invention, the oil feed passage further comprises
oil feed cavities provided to the roller and the vane so as to
communicate with at least one of the first and second oil storage
cavities.
[0023] In the compressor of in accordance with the first embodiment
of the present invention, the oil feed passage is mounted with an
oil feed member for pumping oil up to an oil feeder, with the oil
feed member being twisted in a spiral shape.
[0024] In the compressor of in accordance with the first embodiment
of the present invention, the oil feeder feeds oil through the oil
feed passage by a capillary phenomenon.
[0025] In the compressor of in accordance with the first embodiment
of the present invention, the oil feeder has a groove in an inner
circumferential thereof, and an oil feed member is press fitted
therein except for the groove.
[0026] In the compressor of in accordance with the first embodiment
of the present invention, the oil feed member having a groove in an
outer circumferential surface is press fitted into the oil
feeder.
[0027] A compressor in accordance with the second embodiment of the
present invention further comprises a shaft cover and a main cover
joined to the cylinder type roller and the roller in the axial
direction for defining a compression chamber therebetween, with the
shaft cover covering the axis of rotation, with the main cover
receiving the axis of rotation; a mechanical seal axially joined to
the shaft cover and rotatably supporting the shaft cover onto the
hermetic container; and a bearing axially joined to the main cover
and rotatably supporting the main cover, the axis of rotation and
the roller onto the hermetic container.
[0028] In the compressor of in accordance with the second
embodiment of the present invention, the oil feed passage comprises
an oil feeder formed within the axis of rotation in the axis
direction, and a first oil feed hole radially passing through one
portion of the axis of rotation that is contiguous with the roller
to be in communication with the oil feeder.
[0029] In the compressor of in accordance with the second
embodiment of the present invention, the oil feed passage further
comprises first oil storage cavities formed in the axis of rotation
having the first oil feed hole and in one axial side of the roller,
with the roller being connected to the axis of rotation, so as to
temporarily collect oil supplied through the first oil feed
hole.
[0030] In the compressor of in accordance with the second
embodiment of the present invention, the first oil storage cavities
are formed to lubricate a bearing in contact with an outer
circumferential surface of the axis of rotation and with one axial
side of the second rotating member.
[0031] In the compressor of in accordance with the second
embodiment of the present invention, the oil feed passage further
comprises a second oil feed hole axially passing through the second
rotating member to be in communication with the first oil storage
cavities, and second oil storage cavities formed in the other axial
side of the roller having the second oil feed hole so as to
temporarily collect oil supplied through the second feed hole.
[0032] In the compressor of in accordance with the second
embodiment of the present invention, the second oil storage
cavities are formed to lubricate a bearing in contact with the axis
of rotation and with the other axial side of the roller.
[0033] In the compressor of in accordance with the second
embodiment of the present invention, the shaft cover has cavities
for storing oil which are formed on an opposite side of the second
oil storage cavities.
[0034] In the compressor of in accordance with the second
embodiment of the present invention, the oil feed passage further
comprises oil feed cavities provided to the roller and the vane so
as to communicate with at least one of the first and second oil
storage cavities.
[0035] In the compressor of in accordance with the second
embodiment of the present invention, the oil feed passage is
mounted with an oil feed member for pumping oil up to an oil
feeder, with the oil feed member being twisted in a spiral
shape.
[0036] In the compressor of in accordance with the second
embodiment of the present invention, the oil feeder feeds oil
through the oil feed passage by a capillary phenomenon.
[0037] In the compressor of in accordance with the second
embodiment of the present invention, the oil feeder has a groove in
an inner circumferential thereof, and an oil feed member is press
fitted therein except for the groove.
[0038] In the compressor of in accordance with the second
embodiment of the present invention, the oil feed member having a
groove in an outer circumferential surface is press fitted into the
oil feeder.
[0039] The compressor of the present invention comprises a
refrigerant suction passage for sucking refrigerant into the
compression chamber through the axis of rotation and the roller,
with the refrigerant suction passage formed separately from an oil
feed passage.
Advantageous Effects
[0040] The compressor having the above configuration in accordance
with the present invention arranges the refrigerant passage
separately from the oil passage, so it can prevent the mixing of
refrigerant and oil and further reduce a much refrigerant and oil
leak, thereby guaranteeing an enhanced operational reliability.
Moreover, since the roller and the cylinder rotate together with
the cover, a sliding contact is noticeably reduced so there is no
need to extend the oil feed passage into the interior of the
cylinder. In result, nearly none of the oil is mixed with the
refrigerant, and the operational reliability as well as the
endurance of drive members can be maximized.
[0041] The operational reliability of the compressor is also
enhanced by providing a compressor with an efficient lubrication
structure to evenly distribute lubricating oil over contact
portions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] FIG. 1 is a transverse cross-sectional view showing a
compressor in accordance with a first embodiment of the present
invention;
[0043] FIG. 2 is an exploded perspective view showing one example
of an electromotive part of the compressor in accordance with the
first embodiment of the present invention;
[0044] FIGS. 3 and 4 each illustrate an exploded perspective view
showing one example of the compression mechanism part of the
compressor in accordance with the first embodiment of the present
invention;
[0045] FIG. 5 is a plan view showing a vane mount structure adopted
to a compressor in accordance with the present invention, and a
running cycle of the compressor;
[0046] FIG. 6 is an exploded perspective view showing one example
of a support member of the compressor in accordance with the first
embodiment of the present invention;
[0047] FIGS. 7 through 9 each illustrate a transverse
cross-sectional view showing a rotation centerline of the
compressor in accordance with the first embodiment of the present
invention;
[0048] FIG. 10 is an exploded perspective view showing the
compressor in accordance with the first embodiment of the present
invention;
[0049] FIG. 11 is a transverse cross-sectional view showing how
refrigerant and oil flow in the compressor in accordance with the
first embodiment of the present invention;
[0050] FIGS. 12 and 13 each illustrate a perspective view showing
an example of the assembled structure of a roller and an oil feeder
of the compressor in accordance with the first embodiment of the
present invention;
[0051] FIG. 14 is a perspective view of the roller with an oil feed
structure for a vane and bushes of the compressor in accordance
with the first embodiment of the present invention;
[0052] FIG. 15 is a transverse cross-sectional view showing a first
bearing of the compressor in accordance with the first embodiment
of the present invention;
[0053] FIG. 16 is a transverse cross-sectional view showing a
compressor in accordance with a second embodiment of the present
invention;
[0054] FIG. 17 is an exploded perspective view showing the
compressor in accordance with the second embodiment of the present
invention;
[0055] FIGS. 18 through 20 each illustrate a transverse
cross-sectional view showing a rotation centerline of the
compressor in accordance with the second embodiment of the present
invention;
[0056] FIG. 21 is a transverse cross-sectional view showing how
refrigerant and oil flow in the compressor in accordance with the
second embodiment of the present invention;
[0057] FIGS. 22 and 23 each illustrate a perspective view showing
an example of the assembled structure of a roller and an oil feeder
of the compressor in accordance with the second embodiment of the
present invention; and
[0058] FIG. 24 is a perspective view of the roller with an oil feed
structure for a vane and bushes of the compressor in accordance
with the second embodiment of the present invention.
MODE FOR THE INVENTION
[0059] Hereinafter, preferred embodiments of the present invention
will be described in detail with reference to the accompanying
drawings.
[0060] FIG. 1 is a transverse cross-sectional view showing a
compressor in accordance with the present invention, FIG. 2 is an
exploded perspective view showing one example of an electric motor
of the compressor in accordance with the present invention, and
FIGS. 3 and 4 each illustrate an exploded perspective view showing
one example of a compression mechanism part of the compressor in
accordance with the present invention.
[0061] As shown in FIG. 1, a compressor in accordance with a first
embodiments of the present invention includes a hermetic container
110, a stator 120 installed within the hermetic container 110, a
first rotating member 130 installed within the stator 120 and
rotating by a rotating electromagnetic field from the stator 120, a
second rotating member 140 rotating within the first rotating
member 130 by a rotational force transferred from the first
rotating member 130 for compressing refrigerant therebetween, and
first and second bearings 150 and 160 supporting the first and
second rotating members 130 and 140 to be able to rotate within the
hermetic container 110. An electromotive mechanism part which
provides power through an electrical reaction employs, for example,
a BLDC motor including the stator 120 and the first rotating member
130, and a compression mechanism part which compresses refrigerant
through a mechanical reaction includes the first and second
rotating members 130 and 140, and the first and second bearings 150
and 160. Therefore, by installing the electromotive mechanism part
and the compression mechanism part in a radial direction, the total
height of the compressor can be reduced. Although the embodiments
of the present invention describe a so-called inner rotor type
having the compression mechanism part on the inside of the
electromotive mechanism part as an example, any person of ordinary
skill in the art would easily find out that the general ideal
described above can also be applied conveniently to a so-called
outer rotor type having the compression mechanism part on the
outside of the electromotive mechanism part.
[0062] The hermetic container 110, as shown in FIG. 1, is composed
of a cylinder-shaped body 111, and upper/lower shells 112 and 113
coupled to the top/bottom of the body 111 and stores oil at a
suitable height to lubricate or smooth the first and second
rotating members 130 and 140 (see FIG. 1). The upper shell 113
includes a suction tube 114 at a predetermined position for sucking
refrigerant and a discharge tube 115 at another predetermined
position for discharging refrigerant. Here, whether a compressor is
a high-pressure type compressor or a low-pressure type compressor
is determined depending on whether the interior of the hermetic
container 110 is filled with compressed refrigerants or
pre-compressed refrigerants, and the position of the suction tube
114 and discharge tube 115 should be determined based on that. In
particular, this embodiment of the present invention introduces a
low pressure compressor. To this end, the suction tube 114 is
connected to the hermetic container 110 and the discharge tube 115
is connected to the compression mechanism part. Thus, when a
low-pressure refrigerant is sucked in through the suction tube 114,
it fills the interior of the hermetic container 110 and flows into
the compression mechanism part. In the compression mechanism part,
the low-pressure refrigerant is compressed to high pressure and
then exits outside directly through the discharge tube 115. The
stator 120, as shown in FIG. 2, is composed of a core 121, and a
coil 122 primarily wound around the core 121. While a core used for
a conventional BLDC motor has 9 slots along the circumference, the
core 121 of a BLDC motor has 12 slots along the circumference
because the stator in a preferred embodiment of the present
invention has a relatively a large diameter. Considering that a
coil winding number increases with an increasing number of core
slots, in order to generate an electromagnetic force of the
conventional stator 120, the core 121 may have a smaller
height.
[0063] The first rotating member 130, as shown in FIG. 3, is
composed of a rotor 131, a cylinder 132, a first cover 133 and a
second cover 134. The rotor 131 has a cylindrical shape, with the
rotor 131 rotating within the stator 120 (see FIG. 1) by a rotating
electromagnetic field generated from the stator 120 (see FIG. 1),
and inserted therethrough are plural permanent magnets 131a in an
axial direction to generate a rotating magnetic field. Similar to
the rotor 131, the cylinder 132 also takes the form of a cylinder
to create a compression chamber P (see FIG. 1) inside. The rotor
131 and the cylinder 132 can be manufactured separately and joined
together later. In one example, a pair of mount protrusions 132a is
arranged at the outer circumferential surface of the cylinder 132,
and grooves 131h having a corresponding shape to the mount
protrusions 132a of the cylinder 132 are formed in the inner
circumferential surface of the rotor 131 such that the outer
circumferential surface of the cylinder 132 is engaged with the
inner circumferential surface of the rotor 131. More preferably,
the rotor 131 is integrally formed with the cylinder 132, with the
permanent magnets 131a mounted in holes that are additionally
formed in the axial direction.
[0064] The first cover 133 and the second cover 134 are coupled to
the rotor 131 and/or the cylinder 132 in the axial direction, and
the compression chamber P (see FIG. 1) is defined between the
cylinder 132 and the first and second covers 133 and 134. The first
cover 133 has a planar shape and is provided with a discharge port
133a through which a compressed refrigerant from the compression
chamber P (see FIG. 1) exits and a discharge valve (not shown)
mounted thereon. The second cover 134 is composed of a planar shape
cover 134a, and a downwardly projecting hollow shaft 134b at the
center. The shaft 134b is not absolutely required, but its role in
receiving a load acting thereon increases a contact area with the
second bearing 160 (see FIG. 1) and more stably supports the
rotation of the second cover 134. Since the first and second covers
133 and 134 are bolt-fastened to the rotor 131 or the cylinder 132
in the axial direction, the rotor 131, the cylinder 132, and the
first and second covers 133 and 134 rotate together as one
unit.
[0065] The second rotating member 140, as shown in FIG. 4, is
composed of an axis of rotation 141, a roller 142, and a vane 143.
The axis of rotation 141 is extended in the roller axis direction
from both surfaces of the roller 142, with the axis being projected
further from the bottom surface of the roller 142 than from the top
surface of the roller 142 to provide stable support under any load.
Preferably, the axis of rotation 141 is integrally formed with the
roller 142, but even if they have been manufactured separately,
they must join together to be able to rotate as one unit. As the
axis of rotation 141 takes the form of a hollow shaft with a
blocked center portion, it is better to arrange a suction passage
141a through which refrigerant is sucked in and a passage of an oil
feeder 141b (see FIG. 1) separately from each other so as to
minimize the mixing of oil and refrigerant. The oil feeder 141b
(see FIG. 1) of the axis of rotation 141 is provided with a helical
member to assist oil ascending by a rotational force, or a groove
to assist oil ascending by a capillary action. The axis of rotation
141 and the roller 142 each have all kinds of oil feed holes (not
shown) and oil storage cavities (not shown) for supplying oil from
the oil feeder 141b (see FIG. 1) into between two or more members
subject to sliding interactions. The roller 142 has suction
passages 142a radially penetrating it for the communication of the
suction passage 141a of the axis of rotation 141 with the
compression chamber P (see FIG. 1), such that refrigerant is sucked
into the compression chamber P (see FIG. 1) through the suction
passage 141a of the axis of rotation 141 and the suction passage
142a of the roller 142. The vane 143 is formed on the outer
circumference surface of the roller 142, with the vane 143 being
disposed to extend radially and rotate at a preset angle while
making a linear reciprocating motion, along bushes 144, within a
vane mount slot 132h (see FIG. 5) of the first rotating member 130
(see FIG. 1). As shown in FIG. 5, a couple of bushes 144 limits the
circumferential rotation of the vane 143 to below a preset angle
and guides the vane 143 to make the linear reciprocating motion
through a space defined between the couple of bushes 144 that are
mounted within the vane mount slot 132h (see FIG. 5). Even though
oil may be supplied to enable the vane 143 to attain successful
lubrication while reciprocating linearly within the bushes 144, it
is also possible to make the bushes 144 of natural-lubricating
materials. For example, the bushes 144 can be manufactured in use
of a suitable material sold under the trademark of Vespel SP-21.
Vespel SP-21 is a polymer material which combines excellent wear
resistance, heat resistance, natural lubricity, flame resistance,
and electrical insulation.
[0066] FIG. 5 is a plan view showing a vane mount structure and a
running cycle of the compression mechanism part in a compressor
according to the present invention.
[0067] To explain the mount structure of the vane 143 with
reference to FIG. 5, a vane mount slot 132h is formed axially and
longitudinally in the inner peripheral surface of the cylinder 132,
and a couple of bushes 144 fit into the vane mount slot 132h, and
the vane 143 integrally formed with the axis of rotation 141 and
the roller 142 is inserted between the bushes 144. The cylinder 132
and the roller 142 define the compression chamber P (see FIG. 1)
between them, with the compression chamber P (see FIG. 1) being
divided by the vane 143 into a suction region S and a discharge
region D. As noted earlier, the suction passages 142a (see FIG. 1)
of the roller 142 are positioned in the suction region S, and the
discharge port 133a (see FIG. 1) of the first cover 133 (see FIG.
1) is positioned in the discharge region D, with the suction
passages 142a (see FIG. 1) of the roller 142 and the discharge port
133a (see FIG. 1) of the first cover 133 (see FIG. 1) being
disposed to communicate with a discharge incline portion 136
contiguous with the vane 143. Therefore, the vane 143 which is
integrally manufactured with the roller 142 in the present
invention compressor and assembled to slidably movable between the
bushes 144 can reduce frictional loss caused by the sliding contact
and lower a refrigerant leak between the suction region S and the
discharge region D more than a spring-supported vane which is
manufactured separately from the roller or the cylinder in a
conventional rotary compressor.
[0068] At this time, the rotation of the cylinder shape rotors 131
and 132 is transferred to the vane 143 formed at the second
rotating member 143 so as to rotate the rotating member, and the
bushes 144 inserted into the vane mount slot 132h oscillate,
thereby enabling the cylinder shape rotors 131 and 132 and the
second rotating member 140 to rotate together. While the cylinder
132 and the roller 142 rotate, the vane 143 makes a relatively
linear reciprocating motion with respect to the vane mount slot
132h of the cylinder 132.
[0069] Therefore, when the rotor 131 receives a rotational force
derived from the rotating electromagnetic field of the stator 120
(see FIG. 1), the rotor 131 and the cylinder 132 rotate. With the
vane 143 being inserted into the cylinder 132, the rotational force
of the rotor 131 and the cylinder 132 is transferred to the roller
142. Along the rotation of both, the vane 143 then linearly
reciprocates between the bushes 144. That is, the rotor 131 and the
cylinder 132 each have an inner surface corresponding to the outer
surface of the roller 142, and these corresponding portions are
repeatedly brought into contact with and separate from each other
per rotation of the rotor 131/cylinder 132 and the roller 142. In
so doing the suction region S gradually expands and refrigerant or
a working fluid is sucked into it, while the discharge region D
gradually shrinks at the same time to compress the refrigerant or
working fluid therein and discharge it later.
[0070] To see how the suction, compression and discharge cycle of
the compression mechanism part works, FIG. 5a shows a step of
sucking refrigerant or a working fluid into the suction region S.
For instance, a working fluid is being sucked in and immediately
compressed in the discharge D. When the first and second rotating
members 120 and 140 are arranged as shown in FIG. 5b, the working
fluid is continuously sucked into the suction region S and
compression proceeds accordingly. When the first and second
rotating members 120 and 140 are arranged as shown in FIG. 5c, the
working fluid is continuously sucked in, and the refrigerant or the
working fluid of a preset pressure or higher in the discharge
region D is discharged through the discharge incline portion (or
discharge port) 136. Lastly, when the first and second rotating
members 120 and 140 are arranged as shown in FIG. 5d, the
compression and discharge of the working fluid are finished. In
this way, one cycle of the compression mechanism part is
completed.
[0071] FIG. 6 is an exploded perspective view showing an example of
a support member of the compressor in accordance with the present
invention.
[0072] As shown in FIGS. 1 and 6, the first and second rotating
members 130 and 140 described earlier are rotatably supported on
the inside of the hermetic container 110 by the first and second
bearings 150 and 160 that are coupled in the axial direction. The
first bearing 150 can be secured with a fixing rib or a fixing
protrusion projected from the upper shell 112, and the second
bearing 160 can be bolt-fastened to the lower shell 113.
[0073] The first bearing 150 is constructed to adopt a journal
bearing for rotatably supporting the outer peripheral surface of
the axis of rotation 141 and the inner peripheral surface of the
first cover 133, and a trust bearing for rotatably supporting the
upper surface of the first cover 133. The first bearing 150
includes a suction guide passage 151 communicated with a suction
passage 141a of the axis of rotation 141. The suction guide passage
151 is opened in communication with the interior of the hermetic
container 110 to let the refrigerant having been sucked in through
the suction tube 114 enter the hermetic container 110. Moreover,
the first bearing 150 includes a discharge guide passage 152 which
is opened in communication with the discharge port 133a of the
first cover 133, with the discharge port 133a taking the form of a
ring or an annular ring to accommodate a revolving orbit of the
discharge port 133a of the first cover 133 so as to discharge the
refrigerant coming out through the discharge port 133a of the first
cover 133 via the discharge tube 115 even if the discharge port
133a of the first cover 133 is revolving. Of course, the discharge
guide passage 152 includes a discharge tube mount hole 153 through
which it can be connected directly to the discharge tube 115 for a
direct discharge of the refrigerant outside.
[0074] The second bearing 160 is constructed to adopt a journal
bearing for rotatably supporting the outer peripheral surface of
the axis of rotation 141 and the inner peripheral surface of the
second cover 134, and a trust bearing for rotatably supporting the
lower surface of the roller 142 and the lower surface of the second
cover 134. The second bearing 160 is composed of a planar shape
support 161 that is bolt-fastened to the lower shell 113, and a
shaft 162 disposed at the center of the support 161, with the shaft
having an upwardly protruded hollow 162a. At this time, the center
of the hollow 162a of the second bearing 160 is formed at a
position eccentric from the center of the shaft 162 of the second
bearing 160, with the center of the shaft 162 of the second bearing
160 being collinear with the rotation centerline of the first
rotating member 130, the center of the hollow 162a of the second
bearing 160 being collinear with the axis of rotation 141 of the
second rotating member 140. That is to say, although the center
line of the axis of rotation 141 of the second rotating member 140
can be formed eccentric with respect to the rotation center line of
the first rotating member 130, it can also be formed concentrically
along the longitudinal center line of the roller 142. More details
are now provided below.
[0075] FIGS. 7 through 9 each illustrate a transverse
cross-sectional view showing a rotation centerline of the
compressor in accordance with the first embodiment of the present
invention.
[0076] To enable the first and second rotating members 130 and 140
to compress refrigerant while rotating the second rotating member
140 is positioned eccentric with respect to the first rotating
member 130. One example of relative positioning of the first and
second rotating members 130 and 140 is illustrated in FIGS. 7
through 9. In the drawings, `a` indicates a centerline of the first
axis of rotation of the first rotating member 130, or a
longitudinal centerline of the shaft 134b of the second cover 134,
or a longitudinal centerline of the shaft 162 of the bearing 160.
Here, because the first rotating member 130 includes the rotor 131,
the cylinder 132, the first cover 133 and the second cover 134 as
shown in FIG. 3, with all the elements rotating together en bloc,
`a` may be regarded as the rotation centerline of them, `b`
indicates a centerline of the second axis of rotation of the second
rotating member 140 or a longitudinal centerline of the axis of the
rotation 142, and `c` indicates a longitudinal centerline of the
second rotating member 140 or a longitudinal centerline of the
roller 142.
[0077] As for the preferred embodiment of the present invention
illustrated in FIGS. 1 through 6, FIG. 7 shows that the centerline
`b` of the second axis of rotation is spaced apart a predetermined
distance from the centerline `a` of the first axis of rotation, and
the longitudinal centerline `c` of the second rotating member 140
is collinear with the centerline `b` of the second axis of
rotation. In this way, the second rotating member 140 is disposed
eccentric with respect to the first rotating member 130, and when
the first and second rotating members 130 and 140 rotate together
by the medium of the vane 143, they repeatedly contact, separate,
and retouch per rotation as explained before, thereby varying the
volume of the suction region S/the discharge region D so as to
compress refrigerant within the compression chamber P.
[0078] FIG. 8 shows that the centerline `b` of the second axis of
rotation is spaced apart a predetermined distance from the
centerline `a` of the first axis of rotation, and the longitudinal
centerline `c` of the second rotating member 140 is spaced apart a
predetermined distance from the centerline `b` of the second axis
of rotation, but the centerline `a` of the first axis of rotation
and the longitudinal centerline `c` of the second rotating member
140 are not collinear. Similarly, the second rotating member 140 is
disposed eccentric with respect to the first rotating member 130,
and when the first and second rotating members 130 and 140 rotate
together by the medium of the vane 143, they repeatedly contact,
separate, and retouch per rotation as explained before, thereby
varying the volume of the suction region S/the discharge region D
so as to compress refrigerant within the compression chamber P. As
such, a larger eccentric amount than that in FIG. 7 can be
given.
[0079] FIG. 9 shows that the centerline `b` of the second axis of
rotation is collinear with the centerline `a` of the first axis of
rotation, and the longitudinal centerline `c` of the second
rotating member 140 is spaced apart a predetermined distance from
the centerline `a` of the first axis of rotation and from the
centerline `b` of the second axis of rotation. Similarly, the
second rotating member 140 is disposed eccentric with respect to
the first rotating member 130, and when the first and second
rotating members 130 and 140 rotate together by the medium of the
vane 143, they repeatedly contact, separate, and retouch per
rotation as explained before, thereby varying the volume of the
suction region S/the discharge region D so as to compress
refrigerant within the compression chamber P.
[0080] FIG. 10 is an exploded perspective view showing a compressor
in accordance with one embodiment of the present invention.
[0081] To see an example of how the compressor according to the
first embodiment of the present invention is assembled by referring
to FIGS. 1 and 10, the rotor 131 and the cylinder 132 are either
manufactured separately and then coupled, or manufactured in one
unit from the beginning. The axis of rotation 141, the roller 142
and the vane 143 can also be manufactured separately or integrally,
but either way, they should be able to rotate as one unit. The vane
143 is inserted between the bushes 144 within the cylinder 131.
Overall, the axis of rotation 141, the roller 142 and the vane 143
are mounted within the rotor 131 and the cylinder 132. The first
and second covers 133 and 134 are bolt-fastened in the axial
direction of the rotor 131 and the cylinder 132, with the covers
covering the roller 142 even if the axis of rotation 141 may pass
therethrough.
[0082] After a rotation assembly assembled with the first and
second rotating members 130 and 140 are put together as described
above, the second bearing 160 is bolt-fastened to the lower shell
113, and the rotation assembly is then assembled to the second
bearing 160, with the inner circumferential surface of the shaft
134a of the second cover 134 circumscribing the outer
circumferential surface of the shaft 162, with the outer
circumferential surface of the axis of rotation 141 being inscribed
in the hollow 162a of the second bearing 160. Next, the stator 120
is press fitted into the body 111, and the body 111 is joined to
the upper shell 112, with the stator 120 being positioned to
maintain an air-gap with the outer circumferential surface of the
rotation assembly. After that, the first bearing 150 is joined or
assembled to the upper shell 112 in a way that the discharge tube
115 of the upper shell 112 is press fitted into the discharge mount
hole 153 (see FIG. 6) of the first bearing. As such, the upper
shell 122 assembled with the first bearing 150 is joined to the
body 111, and the first bearing 150 which is fitted between the
axis of rotation 141 and the first cover 133 is covered above by
the shell 112 at the same time. Needless to say, the suction guide
passage 151 of the first bearing 150 is in communication with the
suction passage 141a of the axis of rotation 141, and the discharge
guide passage 152 of the first bearing 150 is in communication with
the discharge port 133a of the first cover 133.
[0083] Therefore, with all of the rotation assembly assembled with
the first and second rotating members 130 and 140, the body 111
mounted with the stator 120, the upper shell 112 mounted with the
first bearing 150, and the lower shell 113 mounted with the second
bearing 160 being joined in the axial direction, the first and
second bearings 150 and 160 rotatably support the rotation assembly
onto the hermetic container 110 in the axial direction.
[0084] FIG. 11 is a transverse cross-sectional view showing how
refrigerant and oil flow in a compressor in accordance with one
embodiment of the present invention.
[0085] To see how the first embodiment of the compressor of the
present invention operates by referring to FIGS. 1 and 11, when
electric current is fed to the stator 120, a rotating
electromagnetic field is generated between the stator 120 and the
rotor 131, and with the application of a rotational force from the
rotor 131, the first rotating member 130, i.e., the rotor 131 and
the cylinder 132, and the first and second covers 133 and 134
rotate together as one unit. As the vane is 134 is installed at the
cylinder 131 to be able to linearly reciprocate, a rotational force
of the first rotating member 130 is transferred to the second
rotating member 140 so the second rotating member 140, i.e., the
axis of rotation 141, the roller 142 and the vane 143, rotate
together as one unit. As shown in FIGS. 7 through 9, because the
first and second rotating members 130 and 140 are disposed
eccentric with respect to each other, they repeatedly contact,
separate, and retouch per rotation, thereby varying the volume of
the suction region S/the discharge region D so as to compress
refrigerant within the compression chamber P and to pump oil at the
same time to lubricate between two slidingly contacting
members.
[0086] During the rotation of the first and second rotating members
130 and 140, oil is supplied to sliding contact portions between
the bearings 150 and 160 and the first and second rotating members
130 and 140, or to sliding contact portions between the first
rotating member 130 and the second rotating member 140, so as to
lubricate between the members. To this end, the axis of rotation
141 is dipped into the oil that is stored at the lower area of the
hermetic container 110, and any kind of oil feed passage for oil
supply is provided to the second rotating member 140. In more
detail, when the axis of rotation 141 starts rotating in the oil
stored at the lower area of the hermetic container 110, the oil
pumps up or ascends along the helical member 145 or groove disposed
within an oil feeder 141b of the axis of the rotation 141 and
escapes through an oil feed hole 141c of the axis of the rotation
141, not only to gather up at an oil storage cavity 141d between
the axis of rotation 141 and the second bearing 160 but also to
lubricate between the axis of rotation 141, the roller 142, the
second bearing 160, and the second cover 134. The oil having been
gathered up at the oil storage cavity 141 d between the axis of
rotation 141 and the second bearing 160 pumps up or ascends through
the oil feed hole 142b of the roller 142, not only to gather up at
oil storage cavities 141e and 142c between the axis of rotation
141, the roller 142 and the first bearing 150, but also to
lubricate between the axis of rotation 141, the roller 142, the
first bearing 150, and the first cover 133.
[0087] FIGS. 12 and 13 each illustrate a perspective view showing
an example of the assembled structure of the roller 142 and oil
feed members 145a and 145b of the compressor in accordance with the
first embodiment of the present invention.
[0088] To see in more detail how oil is fed through the inside of
the axis of rotation 141 by referring to FIG. 11, the bottom of the
hermetic container 110 is filled up with oil, and with one end of
the axis of rotation 141 being dipped into the oil, the oil is
pumped up along the interior of the axis of rotation 141. From this
standpoint, the bottom of the axis of rotation 141 is a start point
of the oil feed passage, playing a role of an oil pump In order for
the axis of rotation 141 to make the oil move up against the
gravity, an oil feed member 145a may be provided to the oil feeder
141b within the axis of rotation 141.
[0089] As for a preferred embodiment, the oil fee member 145a may
take the form of a helical shape to function as a centrifugal pump
for example. The helical oil feed member can be prepared by
twisting a roughly rectangular board in a spiral form. In such
case, the board may be twisted to the left or right to help the oil
climb up along the face of the board according to the rotational
direction of the axis of rotation 141. Besides the helical shape,
the oil feed member may also take the form of a pillar shape with a
helical groove formed in its outer circumferential surface, or a
propeller shape. The helical oil feed member 145a rotates together
with the axis of rotation 141 within the oil feeder 141b to pump up
oil by the rotational force.
[0090] FIG. 13 shows yet another preferred embodiment of the oil
feed member 145b, with the oil feeder 141b pumping up oil using a
capillary phenomenon. To induce the capillary phenomenon, a pillar
shape oil feed member 145b is press fitted into the oil feeder 141b
within the axis of rotation 141, and plural grooves 145c with a
diameter small enough for the capillary process to take place
between the inner circumferential surface of the axis of rotation
141 and the oil feed member are formed. Needless to say, the
grooves 145c may be formed in the inner circumferential surface of
the oil feeder 141b, or one side of the oil feed member 145b, or
both sides.
[0091] Moreover, there is provided an oil feed passage
communicating with peripheral area and the roller 142 to evenly
distribute the oil having been pumped up along the axis of rotation
141. As such, the oil feeder 141b has one end blocked to prevent
the mixing of oil into the refrigerant in an area close to the
roller 142 in the axial direction, and an oil feed hole 141c is
drilled, passing through the axis of rotation 141 located
contiguous with the roller 142. The oil flowing out through the oil
feed hole 141c is fed between the outer circumferential surface of
the axis of rotation 141 and the second bearing 160, and between
the roller 142 and the second cover 134, thereby forming a film of
a uniform thickness for lubrication. The second cover 134 has a
collection cavity to collect the oil having been used for
lubricating between the roller 142 and the contact surface to the
bottom of the hermetic container 110.
[0092] In addition, an oil storage cavity 141d is formed between
the axis of rotation 141 and the second bearing 160 to serve as a
temporal reservoir of the oil flowing out from the oil feed hole
141c. Meanwhile, the roller 142 has an oil feed hole 142b that is
drilled in the axial direction to be in communication with the oil
storage cavity 141d. Thus, the rotational friction of the axis of
rotation 141 is lubricated through oil in the oil storage cavity
141e that is formed between the outer circumferential surface of
the axis of rotation 141 and the first bearing 150 at the upper
portion of the roller, and the oil is temporarily collected in the
oil storage cavity 142c between the roller 142 and the first
bearing 150 and used later for lubricating the friction between the
roller 142 and the first bearing 150 or the first cover 133.
[0093] FIG. 14 shows one embodiment of the construction to feed oil
to the vane 143 and the bushes 144 in accordance with the present
invention, with the oil being fed between the vane 143 and the
bushes 144 through an oil groove 143a or an oil hole. Preferably,
the passage going through the vane 143 and the bushes 144 is formed
extendedly from the oil storage cavity 142c placed contiguous with
the upper portion of the roller of the axis of rotation 141. In so
doing oil flows down, by the gravity, along the vane 143 and the
bushes 144 from the upper side of the roller 141 evenly to achieve
lubrication. Optionally, instead of adopting the above
configuration, the bushes 144 may be made of natural-lubricating
materials.
[0094] The refrigerant flow will now be explained in details based
on FIGS. 1 and 9.
[0095] When the first and second rotating members 130 and 140
rotate by the medium of the vane 143, refrigerant is sucked in,
compressed and discharged. In more detail, the roller 142 and the
cylinder 132 repeatedly contact, separate, and retouch, thereby
varying the volume of the suction region and the discharge region
divided by the vane 143 within the compression chamber P so as to
suck in, compress, and discharge refrigerant. That is to say, as
the volume of the suction region gradually expands, refrigerant is
sucked into the suction region of the compression chamber P through
the suction tube 114 of the hermetic container 110, the interior of
the hermetic container 110, the suction guide passage 151 of the
first bearing 150, the suction passage 141a of the axis of rotation
141 and the suction passage 142a of the roller 142. Concurrently,
as the volume of the discharge region gradually shrinks along the
motions of the roller 142 and the cylinder 132, refrigerant is
compressed, and when a discharge valve (not shown) is open at a
pressure above the preset level the compressed refrigerant is then
discharged in the direction of the first cover 133 through the
discharge incline portion 136 (see FIG. 5). The discharged
refrigerant eventually exits outside of the hermetic container 110
through the discharge port 133b of the first cover 133, the
discharge guide passage 152 of the first bearing 150, and the
discharge tube 115 of the hermetic container 110.
[0096] FIG. 15 shows a cross section of the first bearing 150.
[0097] Refrigerant having passed through the suction guide passage
151 is sucked in axially through the suction passage 141a (see FIG.
11) which is the hollow shaft portion on the upper side of the
roller 142 (see FIG. 11) and undergoes the compression process in
the compression chamber P as described above. The refrigerant
having gone through the compression process passes the discharge
port 133a (see FIG. 11) of the first cover 133 (see FIG. 11) and is
discharged to the discharge tube 115 via the discharge guide
passage 152. Referring to FIG. 11, because the first bearing 150
supports the motion of the axis of rotation 141 of the roller 142,
to accommodate the compressed refrigerant being discharged through
the discharge port 133a (see FIG. 11), the discharge guide passage
152 creates a space circumscribing the axis of rotation 141. The
space created by the discharge guide passage 152 may function as a
muffler for reducing noise associated with the refrigerant
compression.
[0098] In reference to FIGS. 16 through 24, the following now
explains in detail about a compressor in accordance with a second
embodiment of the present invention.
[0099] FIG. 16 is a transverse cross-sectional view showing a
compressor in accordance with the second embodiment of the present
invention.
[0100] As shown in FIG. 16, the compressor in accordance with the
second embodiment of the present invention includes a hermetic
container 210, a stator 220 installed within the hermetic container
210, a first rotating member 230 installed within the stator 220
and rotating with an interaction with the stator 220, a second
rotating member 240 rotating within the first rotating member 230
by a rotational force transferred from the first rotating member
230 for compressing refrigerant therebetween, a muffler 250 for
guiding refrigerant suction/discharge to a compression chamber P
between the first and second rotating members 230 and 240, a
bearing 260 supporting the first and second rotating members 230
and 240 to be able to rotate within the hermetic container 210, and
a mechanical seal 270. An electromotive mechanism part employs, for
example, a BLDC motor including the stator 220 and the first
rotating member 230, and a compression mechanism part includes the
first and second rotating members 230 and 240, the muffler 250, the
bearing 260 and the mechanical seal 270. Therefore, by increasing
inner diameter of the electromotive mechanism part instead of
reducing its height, the compression mechanism part can be arranged
within the electromotive mechanism part, thereby lowering the total
height of the compressor. The hermetic container 210 is composed of
a cylinder-shaped body 211, and upper/lower shells 212 and 213
coupled to the top/bottom of the body 211 and stores oil at a
suitable height to lubricate or smooth the first and second
rotating members 230 and 240. The upper shell 213 includes a
suction tube 214 on one side for sucking refrigerant, and a
discharge tube 215 at the center for discharging refrigerant. Here,
whether a compressor is a high-pressure type compressor or a
low-pressure type compressor is determined depending on the
connection structure of the suction tube 214 and the discharge tube
215. This particular embodiment of the invention introduces a low
pressure compressor, wherein the suction tube 214 is connected to
the hermetic container 210 and the discharge tube 215 is connected
directly to the compression mechanism part. Thus, when a
low-pressure refrigerant is sucked in through the suction tube 214,
it fills the interior of the hermetic container 210 and flows into
the compression mechanism part through the suction tube 215.
[0101] The stator 220 is composed of a core 221, and a coil 222
primarily wound around the core 221. Since the stator 220 has the
same construction with the compressor stator in accordance with the
first embodiment of the present invention, it will not be explained
here.
[0102] FIG. 17 is an exploded perspective view showing the
compressor in accordance with the second embodiment of the present
invention.
[0103] The first rotating member 230, as shown in FIG. 17, is
composed of a rotor 231, a cylinder 232, a shaft cover 233 and a
cover 234. The rotor 231 has a cylindrical shape, with the rotor
231 rotating within the stator 220 by a rotating electromagnetic
field generated from the stator 220, and inserted therethrough are
plural permanent magnets (not shown) in an axial direction to
generate a rotating magnetic field Similar to the rotor 231, the
cylinder 232 also takes the form of a cylinder to create a
compression chamber P inside. The rotor 231 and the cylinder 232
can be manufactured separately and joined together later, or can be
integrally formed from the beginning.
[0104] The shaft cover 233 and the main cover 234 are coupled to
the rotor 231 or the cylinder 232 in the axial direction, and the
compression chamber P is defined between the cylinder 232 and the
shaft cover 233 and the main cover 234. The shaft cover 233 is
composed of a planar shape cover portion 233A for covering the
upper surface of the roller 242, and a downwardly projecting hollow
shaft 233B at the center. The cover portion 233A of the shaft cover
233 includes a suction port 233a for sucking in refrigerant
therethrough, a discharge port 233b for discharging a compressed
refrigerant therethrough from the compression chamber P, and a
discharge valve (not shown) mounted thereon. The shaft 233B of the
shaft cover 233 includes discharge guide passages 233c and 233d for
guiding refrigerant to the outside of the hermetic container 210,
with the refrigerant having been discharged through the discharge
port 233b of the shaft cover 233. Also, the shaft 233B is designed
to be inserted into the mechanical seal 270 by forming part of its
outer circumferential surface at the tip. Similar to the shaft
cover 233, the main cover 234 is composed of a planar shape cover
portion 234a for covering the lower surface of the roller 242, and
a downwardly projecting hollow shaft portion 234b at the center.
Although the shaft portion 234b may be optionally omitted, its role
in receiving a load acting thereon increases a contact area with
the bearing 260 and give more stable support to the main cover 234.
Since the shaft cover 233 and the main cover 234 are bolt-fastened
to the rotor 231 or the cylinder 232 in the axial direction, the
rotor 231, the cylinder 232, and the shaft cover and the main cover
233 and 234 rotate together as one unit. Moreover, the muffler 250,
which includes a suction chamber 251 communicated with the suction
port 233a of the shaft cover and a discharge chamber 252
communicated with the discharge port 233b and the discharge guide
passages 233c and 233d of the shaft cover 233, with the suction
chamber 251 being defined separately from the discharge chamber
252, is also joined in the axial direction of the shaft cover 233.
Of course, the suction chamber 251 of the muffler 250 may be
omitted, but it is better for the muffler 250 to have the suction
chamber with the suction port 251a to be able to suck the
refrigerant within the hermetic container 210 into the suction port
233a of the shaft cover 233.
[0105] The second rotating member 240 is composed of an axis of
rotation 241, a roller 242, and a vane 243. The axis of rotation
241 is protrusively formed towards one side, i.e., lower surface,
in the roller 242 axis direction. Because the axis of rotation 241
is protruded only from the lower surface, its protruded length is
longer than that in the case where the axis of rotation is
protruded from both the upper and lower surfaces so it can support
the motion of the second rotating member more stably. Also, even if
the axis of rotation 241 and the roller 242 may have been
manufactured separately, they must join together to be able to
rotate as one unit. The axis of rotation 241 takes the form of a
hollow shaft passing through the inside of the roller 242, with the
hollow being composed of an oil feeder 241a for pumping oil. Here,
the oil feeder 241a of the axis of rotation 241 is provided with a
helical member to assist oil ascending by a rotational force, or a
groove to assist oil ascending by a capillary phenomenon. The axis
of rotation 241 and the roller 242 each have all kinds of oil feed
holes 241b and oil storage grooves 242b and oil storage cavities
242a and 242c for supplying oil from the oil feeder 241a into
between two or more members subject to sliding interactions.
[0106] The vane mount structure and a running cycle of the cylinder
232 and the roller 242 are the same as those in the first
embodiment.
[0107] The first and second rotating members 230 and 240 described
earlier are rotatably supported on the inside of the hermetic
container 210 by the bearing 260 and the mechanical seal 270 that
are coupled in the axial direction. The bearing 260 is
bolt-fastened to the lower shell 213, and the mechanical seal 270
is secured to the inside of the hermetic container 210 by welding
or the like in communication with the discharge tube 215 of the
hermetic container 210.
[0108] The mechanical seal 270 is a device for preventing a fluid
leak because of the contact between a rapidly spinning shaft and a
fixed element/rotatory element in general, and is disposed between
the discharge tube 215 of the stationary hermetic container 210 and
the rotating shaft 233B of the shaft cover 233. Here, the
mechanical seal 270 rotatably supports the shaft cover within the
hermetic container 210 and communicates the shaft 233B of the shaft
cover 233 with the discharge tube 215 of the hermetic container
210, while preventing a refrigerant leak between them.
[0109] The bearing 260 is constructed to adopt a journal bearing
for rotatably supporting the outer peripheral surface of the axis
of rotation 241 and the inner peripheral surface of the main cover
234, and a trust bearing for rotatably supporting the lower surface
of the roller 242 and the lower surface of the main cover 234. The
bearing 260 is composed of a planar shape support 261 that is
bolt-fastened to the lower shell 213, and a shaft 262 disposed at
the center of the support 261, with the shaft having an upwardly
protruded hollow 262a (see FIG. 17). At this time, the center of
the hollow 262a of the bearing 260 is formed at a position
eccentric from the center of the shaft 262 of the bearing 260, or
may be collinear with the center of the shaft 262 of the bearing
260 depending on whether the roller 242 is formed eccentric. More
details are now provided below.
[0110] FIGS. 18 through 20 each illustrate a transverse
cross-sectional view showing a rotation centerline of the
compressor in accordance with the second embodiment of the present
invention.
[0111] To enable the first and second rotating members 230 and 240
to compress refrigerant while rotating the second rotating member
240 is positioned eccentric with respect to the first rotating
member 230. One example of relative positioning of the first and
second rotating members 230 and 240 is illustrated in FIGS. 18
through 20. In the drawings, `a` indicates a centerline of the
first axis of rotation of the first rotating member 230, or it may
be regarded as a longitudinal centerline of the shaft 234b of the
main cover 234, or a longitudinal centerline of the shaft 262 of
the bearing 260. Here, because the first rotating member 230
includes the rotor 231, the cylinder 232, the shaft cover 233 and
the main cover 234 as shown in this embodiment, with all the
elements rotating together en bloc, `a` may be regarded as the
rotation centerline of them, `b` indicates a centerline of the
second axis of rotation of the second rotating member 240 or a
longitudinal centerline of the axis of the rotation 241, and `c`
indicates a longitudinal centerline of the second rotating member
240 or a longitudinal centerline of the roller 242.
[0112] FIG. 18 shows that the centerline `b` of the second axis of
rotation is spaced apart a predetermined distance from the
centerline `a` of the first axis of rotation, and the longitudinal
centerline `c` of the second rotating member 240 is collinear with
the centerline `b` of the second axis of rotation. In this way, the
second rotating member 240 is disposed eccentric with respect to
the first rotating member 230, and when the first and second
rotating members 230 and 240 rotate together by the medium of the
vane 243, they repeatedly contact, separate, and retouch per
rotation as explained before, thereby compressing refrigerant
within the compression chamber, as in this embodiment.
[0113] FIG. 19 shows that the centerline `b` of the second axis of
rotation is spaced apart a predetermined distance from the
centerline `a` of the first axis of rotation, and the longitudinal
centerline `c` of the second rotating member 240 is spaced apart a
predetermined distance from the centerline `b` of the second axis
of rotation, but the centerline `a` of the first axis of rotation
and the longitudinal centerline `c` of the second rotating member
240 are not collinear. Similarly, the second rotating member 240 is
disposed eccentric with respect to the first rotating member 230,
and when the first and second rotating members 230 and 240 rotate
together by the medium of the vane 243, they repeatedly contact,
separate, and retouch per rotation as explained before in the first
embodiment, thereby compressing refrigerant within the compression
chamber, as in this embodiment.
[0114] FIG. 20 shows that the centerline `b` of the second axis of
rotation is collinear with the centerline `a` of the first axis of
rotation, and the longitudinal centerline `c` of the second
rotating member 240 is spaced apart a predetermined distance from
the centerline `a` of the first axis of rotation and from the
centerline `b` of the second axis of rotation. Similarly, the
second rotating member 240 is disposed eccentric with respect to
the first rotating member 230, and when the first and second
rotating members 230 and 240 rotate together by the medium of the
vane 243, they repeatedly contact, separate, and retouch per
rotation as explained before in the first embodiment, thereby
compressing refrigerant within the compression chamber, as in this
embodiment.
[0115] To see an example of how the compressor according to one
embodiment of the present invention is assembled by referring to
FIGS. 16 and 17, the rotor 231 and the cylinder 232 are either
manufactured separately and then coupled, or manufactured in one
unit from the beginning. The axis of rotation 241, the roller 242
and the vane 243 can also be manufactured separately or integrally,
but either way, they should be able to rotate as one unit. The vane
243 is inserted between the bushes 244 within the cylinder 231.
Overall, the axis of rotation 241, the roller 242 and the vane 243
are mounted within the rotor 231 and the cylinder 232. The shaft
cover 233 and the main cover 234 are bolt-fastened in the axial
direction of the rotor 231 and the cylinder 232, with the shaft
cover 233 covering the upper surface of the roller 242 while the
main cover 234 covering the roller 242 even if the axis of rotation
241 may pass through the main cover 234. In addition, the muffler
250 is bolt-fastened in the axial direction of the shaft cover 233,
with the shaft 233B of the shaft cover 233 fitting into a shaft
cover mount hole 253 of the muffler 250 to pass through the muffler
250. To prevent a refrigerant leak between the shaft cover 233 and
the muffler 250, a separate sealing member (not shown) may be
provided additionally to the joint area between the shaft cover 233
and the muffler 250.
[0116] After a rotation assembly assembled with the first and
second rotating members 230 and 240 are put together as described
above, the bearing 260 is bolt-fastened to the lower shell 213, and
the rotation assembly is then assembled to the bearing 260, with
the inner circumferential surface of the shaft 234a of the main
cover 234 circumscribing the outer circumferential surface of the
shaft 262 of the bearing 260, with the outer circumferential
surface of the axis of rotation 241 being inscribed in the hollow
262a of the bearing 260. Next, the stator 220 is press fitted into
the body 211, and the body 211 is joined to the upper shell 212,
with the stator 220 being positioned to maintain an air-gap with
the outer circumferential surface of the rotation assembly. After
that, the mechanical seal 270 is assembled within the upper shell
212 in a way that it is communicated with the discharge tube 215,
and the upper shell 212 having the mechanical seal 270 being
secured thereon is joined to the body 211, with the mechanical seal
270 being inserted into a stepped portion on the outer
circumferential surface of the shaft 233B of the shaft cover 233.
Of course, the mechanical seal 270 is assembled to enable the
communication between the shaft 233B of the shaft cover 233 and the
discharge tube 215 of the upper shell 212.
[0117] Therefore, with all of the rotation assembly assembled with
the first and second rotating members 230 and 240, the body 211
mounted with the stator 220, the upper shell 212 mounted with the
mechanical seal 270, and the lower shell 213 mounted with the
bearing 260 being joined in the axial direction, the mechanical
seal 270 and the bearing 260 rotatably support the rotation
assembly onto the hermetic container 210 in the axial
direction.
[0118] FIG. 21 is a transverse cross-sectional view showing how
refrigerant and oil flow in the compressor in accordance with the
second embodiment of the present invention.
[0119] To see how the compressor according to the second embodiment
of the present invention operates by referring to FIGS. 16 and 21,
when electric current is fed to the stator 220, a rotating
electromagnetic field is generated between the stator 220 and the
rotor 231, and with the application of a rotational force from the
rotor 231, the first rotating member 230, i.e., the rotor 231 and
the cylinder 232, and the shaft cover 233 and the main cover 234
rotate together as one unit. As the vane is 234 is installed at the
cylinder 231 to be able to linearly reciprocate, a rotational force
of the first rotating member 230 is transferred to the second
rotating member 240 so the second rotating member 240, i.e., the
axis of rotation 241, the roller 242 and the vane 243, rotate
together as one unit. As shown in FIGS. 18 through 20, because the
first and second rotating members 230 and 240 are disposed
eccentric with respect to each other, they repeatedly contact,
separate, and retouch, thereby varying the volume of the suction
region/the discharge region divided by the vane 243 so as to
compress refrigerant and to pump oil at the same time to lubricate
between two slidingly contacting members.
[0120] Moreover, during the rotation of the first and second
rotating members 230 and 240, oil is supplied to sliding contact
portions between the bearing 260 and the first and second rotating
members 230 and 240 to lubricate between the members. To this end,
the axis of rotation 241 is dipped into the oil that is stored at
the lower area of the hermetic container 210, and any kind of oil
feed passage for oil supply is provided to the second rotating
member 240. In more detail, when the axis of rotation 241 starts
rotating while being dipped in the oil stored at the lower area of
the hermetic container 210, the oil pumps up or ascends along the
helical member 245a or grooves 245c disposed within an oil feeder
241a of the axis of the rotation 241 and flows out through an oil
feed hole 24 lb of the axis of the rotation 241, not only to gather
up at an oil storage cavity 241c between the axis of rotation 241
and the bearing 260, but also to lubricate between the axis of
rotation 241, the roller 242, the bearing 260, and the main cover
234. Also, the oil having been gathered up at the oil storage
cavity 241c between the axis of rotation 241 and the bearing 260
pumps up or ascends through the oil feed hole 242b of the roller
242, not only to gather up at oil storage cavities 233e and 242c
between the axis of rotation 241, the roller 242 and the first
cover 233, but also to lubricate between the axis of rotation 241,
the roller 242, the shaft cover 233.
[0121] FIGS. 22 and 23 each illustrate a perspective view of an
example of how the roller 242 and the oil feed member 245 are
assembled in the compressor in accordance with the second
embodiment of the present invention.
[0122] To see in more detail how oil is fed through the inside of
the axis of rotation 241 by referring to FIG. 21, the bottom of the
hermetic container 210 is filled up with oil, and with one end of
the axis of rotation 241 being dipped into the oil, the oil is
pumped up along the interior of the axis of rotation 241. From this
standpoint, the bottom of the axis of rotation 241 is a start point
of the oil feed passage, playing a role of an oil pump. In order
for the axis of rotation 241 to make the oil move up against the
gravity, an oil feed member 245a may be provided to the oil feeder
241b within the axis of rotation 241.
[0123] As for a preferred embodiment, the oil fee member 245a may
take the form of a helical shape to function as a centrifugal pump
for example. The helical oil feed member can be prepared by
twisting a roughly rectangular board in a spiral form. In such
case, the board may be twisted to the left or right to help the oil
climb up along the face of the board according to the rotational
direction of the axis of rotation 241. Optionally, the oil feed
member may also take the form of a pillar shape with a helical
groove formed in its outer circumferential surface, or a propeller
shape. The helical oil feed member 245a rotates together with the
axis of rotation 141 within the oil feeder 241b to pump up oil by
the rotational force.
[0124] FIG. 23 shows yet another preferred embodiment of the oil
feed member 245b, with the oil feeder 241a pumping up oil using a
capillary phenomenon. To induce the capillary phenomenon, a pillar
shape oil feed member 245b is press fitted into the oil feeder 241a
within the axis of rotation 241, and plural grooves 245c with a
diameter small enough for the capillary process to take place
between the inner circumferential surface of the axis of rotation
241 and the oil feed member are formed. Needless to say, the
grooves 245c may be formed in the inner circumferential surface of
the oil feeder 241a, or one side of the oil feed member 245b, or
both sides.
[0125] Moreover, there is provided an oil feed passage
communicating with peripheral area and the roller 242 to evenly
distribute the oil having been pumped up along the axis of rotation
241. In this embodiment, a refrigerant suction passage is
separately formed above the roller 242, with the axis of rotation
241 being integrally formed with the roller 241 underneath it, and
an oil passage is formed on the lower side (i.e. below the roller
242 of the axis of rotation 241). In so doing the oil feeder 241a
is arranged even in the interior of the roller 242 in the axial
direction, and the roller has one end blocked inside. The blocked
end of the roller may be covered by the cover portion 233A of the
shaft cover 233, or the upper side of the roller may optionally be
blocked. In this way, the oil feed hole 241b is drilled, radially
passing through the axis of rotation 241 located contiguous with
the lower side of the roller 242. The oil flowing out through the
oil feed hole 241c is fed between the outer circumferential surface
of the axis of rotation 241 and the second bearing 260, and between
the roller 242 and the second cover 234, thereby forming an oil
film of a uniform thickness for lubrication. The second cover 234
has a collection cavity to collect the oil having been used for
lubricating between the roller 242 and the contact surface to the
bottom of the hermetic container 210.
[0126] In addition, an oil storage cavity 241c is formed between
the axis of rotation 241 and the second bearing 260 to serve as a
temporal reservoir of the oil flowing out from the oil feed hole
241b. Meanwhile, the roller 242 has an oil feed hole 242b that is
drilled in the axial direction to be in communication with the oil
storage cavity 241c, so the oil is temporarily collected at the oil
storage cavities 233e and 242c formed between the shaft cover 233
and the roller 233 and then used for lubrication of friction
between the roller 242 and the shaft cover 233. In detail, the oil
which is supplied directly from the oil feeder 241a and the oil
which is supplied through the oil feed hole 242b are temporarily
stored at the oil storage cavity 233e formed in the roller 242 and
the oil storage cavity 242c formed in the shaft cover 233
contacting the roller 242, and then form an oil film between the
roller 242 and the shaft cover 233 to lubricate the friction
between them.
[0127] Optionally, it is possible to extend the oil feeder 242a of
the compressor of the second embodiment of the present invention up
to the height of a contact portion between the roller 242 and the
shaft cover 233 and feed oil directly to the oil storage cavities
233e and 242c. In this case, the oil feed hole 242b may not
necessarily drilled in the roller 242.
[0128] FIG. 24 shows one embodiment of the construction to feed oil
to the vane 243 and the bushes 244 in accordance with the second
embodiment of the present invention, with the oil being fed between
the vane 243 and the bushes 244 through an oil groove 243a or an
oil hole. Preferably, the passage going through the vane 243 and
the bushes 244 is formed extendedly from the oil storage cavities
233e and 242c placed contiguous with the upper portion of the
roller 242. In so doing oil flows down, by the gravity, along the
vane 243 and the bushes 244 from the upper side of the roller 241
evenly to achieve lubrication. Optionally, instead of adopting the
above configuration, the bushes 244 may be made of
natural-lubricating materials.
[0129] According to this embodiment of the invention, because the
roller 242, the cylinder 232, the shaft cover 233 and the main
cover 234 rotate together, a frictional loss becomes small. In more
detail, unlike the conventional techniques, the sliding contact
between the cylinder 232 and the roller 242 is noticeably reduced
by rotating the roller 242, the cylinder 232, the shaft cover 233
and the main cover 234 together with the rotor 231. Furthermore,
the friction between the roller 242 and the shaft cover/cover
233/234 is relatively smaller than that of the conventional
compressors. This is primarily because the roller 242 of the
present invention compressor makes a translational motion at the
contact surface with the shaft cover 233/cover 234, unlike the
conventional roller making both rotational and translational
motions between the covers. Thus, there is no need to extend the
oil feed passage of the present invention compressor into the
interior of the cylinder 232, and this assures that the oil will
hardly mix with the refrigerant. If so, a separate installation of
an accumulator can be omitted, and the compressor can be
manufactured in a simple structure and with an enhanced operational
reliability.
[0130] The refrigerant flow will now be explained in details based
on FIGS. 16 and 21.
[0131] When the first and second rotating members 230 and 240
rotate by the medium of the vane 243, refrigerant is sucked in,
compressed and discharged. In more detail, the roller 242 and the
cylinder 232 repeatedly contact, separate, and retouch during the
motion of the first and second rotating members 230 and 240,
thereby varying the volume of the suction region and the discharge
region divided by the vane 243 so as to suck in, compress, and
discharge refrigerant. That is to say, as the volume of the suction
region gradually expands according to the rotation of both,
refrigerant is sucked into the suction region of the compression
chamber P through the suction tube 214 of the hermetic container
210, the interior of the hermetic container 210, the suction port
251a and suction chamber 251 of the muffler 250, and the suction
port 233a of the shaft cover 233.
[0132] With the refrigerant being sucked into the suction region,
the volume of the discharge region gradually shrinks along the
motions of the roller 242 and the cylinder 232, refrigerant is
compressed, and when a discharge valve (not shown) is open at a
pressure above the preset level the compressed refrigerant is then
discharged in the direction of the shaft cover 233 through the
discharge incline part 236 (see FIG. 17). The discharged
refrigerant flows into the discharge chamber 252 of the muffler 250
through the discharge port 233b of the shaft cover 233. The noise
level is reduced as the high-pressure refrigerant passes through
the discharge chamber 252 of the muffler 250. The refrigerant flow
inducing a lower noise is eventually exits outside of the hermetic
container 210 through the discharge passages 233c and 233d formed
in the shaft of the shaft cover 233, and the discharge tube 215 of
the hermetic container 210.
[0133] With the compressor having the above configuration in
accordance with the present invention, lubrication is done smoothly
in presence of the oil feed passage at the contact surface between
drive members. In addition, because the refrigerant suction passage
and the refrigerant discharge passage circulate in separation from
the oil circulation passage, it is possible to isolate the
refrigerant passage from the oil passage. Accordingly, the
possibility of the mixing of oil into refrigerant is minimized, and
the compressor of high oil recovery can be provided. Besides, a
much oil and refrigerant leak is reduced to thus guarantee an
enhanced operational reliability.
[0134] Moreover, because the roller 142, 242, the cylinder 132,
232, and the cover 133, 134, 233, 234 according to the embodiment
of the invention rotate together, a frictional loss becomes small.
In more detail, unlike the conventional techniques, the sliding
contact between the cylinder 132, 232 and the roller 142, 242 is
noticeably reduced by rotating the roller 142, 242, the cylinder
132, 232, the cover 133, 134, 233, 234 together with the rotor 131,
231. In addition, the friction between the roller and the cover is
relatively smaller than that of the conventional compressors. This
is primarily because the roller of the present invention compressor
makes a translational motion at the contact surface with the cover,
unlike the conventional roller making both rotational and
translational motions between the covers. Therefore, there is no
need to extend the oil feed passage of the present invention
compressor into the interior of the cylinder 132, 232, and this
assures that the oil will hardly mix with the refrigerant. If so, a
separate installation of an accumulator can be omitted, and the
compressor can be manufactured in a simple structure and with an
enhanced operational reliability.
[0135] The present invention has been described in detail with
reference to the embodiments and the attached drawings. However,
the scope of the present invention is not limited to the
embodiments and the drawings, but defined by the appended
claims.
* * * * *